---
_id: '10293'
abstract:
- lang: eng
text: "Indirect reciprocity in evolutionary game theory is a prominent mechanism
for explaining the evolution of cooperation among unrelated individuals. In contrast
to direct reciprocity, which is based on individuals meeting repeatedly, and conditionally
cooperating by using their own experiences, indirect reciprocity is based on individuals’
reputations. If a player helps another, this increases the helper’s public standing,
benefitting them in the future. This lets cooperation in the population emerge
without individuals having to meet more than once. While the two modes of reciprocity
are intertwined, they are difficult to compare. Thus, they are usually studied
in isolation. Direct reciprocity can maintain cooperation with simple strategies,
and is robust against noise even when players do not remember more\r\nthan their
partner’s last action. Meanwhile, indirect reciprocity requires its successful
strategies, or social norms, to be more complex. Exhaustive search previously
identified eight such norms, called the “leading eight”, which excel at maintaining
cooperation. However, as the first result of this thesis, we show that the leading
eight break down once we remove the fundamental assumption that information is
synchronized and public, such that everyone agrees on reputations. Once we consider
a more realistic scenario of imperfect information, where reputations are private,
and individuals occasionally misinterpret or miss observations, the leading eight
do not promote cooperation anymore. Instead, minor initial disagreements can proliferate,
fragmenting populations into subgroups. In a next step, we consider ways to mitigate
this issue. We first explore whether introducing “generosity” can stabilize cooperation
when players use the leading eight strategies in noisy environments. This approach
of modifying strategies to include probabilistic elements for coping with errors
is known to work well in direct reciprocity. However, as we show here, it fails
for the more complex norms of indirect reciprocity. Imperfect information still
prevents cooperation from evolving. On the other hand, we succeeded to show in
this thesis that modifying the leading eight to use “quantitative assessment”,
i.e. tracking reputation scores on a scale beyond good and bad, and making overall
judgments of others based on a threshold, is highly successful, even when noise
increases in the environment. Cooperation can flourish when reputations\r\nare
more nuanced, and players have a broader understanding what it means to be “good.”
Finally, we present a single theoretical framework that unites the two modes of
reciprocity despite their differences. Within this framework, we identify a novel
simple and successful strategy for indirect reciprocity, which can cope with noisy
environments and has an analogue in direct reciprocity. We can also analyze decision
making when different sources of information are available. Our results help highlight
that for sustaining cooperation, already the most simple rules of reciprocity
can be sufficient."
alternative_title:
- ISTA Thesis
article_processing_charge: No
author:
- first_name: Laura
full_name: Schmid, Laura
id: 38B437DE-F248-11E8-B48F-1D18A9856A87
last_name: Schmid
orcid: 0000-0002-6978-7329
citation:
ama: Schmid L. Evolution of cooperation via (in)direct reciprocity under imperfect
information. 2021. doi:10.15479/at:ista:10293
apa: Schmid, L. (2021). Evolution of cooperation via (in)direct reciprocity under
imperfect information. Institute of Science and Technology Austria. https://doi.org/10.15479/at:ista:10293
chicago: Schmid, Laura. “Evolution of Cooperation via (in)Direct Reciprocity under
Imperfect Information.” Institute of Science and Technology Austria, 2021. https://doi.org/10.15479/at:ista:10293.
ieee: L. Schmid, “Evolution of cooperation via (in)direct reciprocity under imperfect
information,” Institute of Science and Technology Austria, 2021.
ista: Schmid L. 2021. Evolution of cooperation via (in)direct reciprocity under
imperfect information. Institute of Science and Technology Austria.
mla: Schmid, Laura. Evolution of Cooperation via (in)Direct Reciprocity under
Imperfect Information. Institute of Science and Technology Austria, 2021,
doi:10.15479/at:ista:10293.
short: L. Schmid, Evolution of Cooperation via (in)Direct Reciprocity under Imperfect
Information, Institute of Science and Technology Austria, 2021.
date_created: 2021-11-15T17:12:57Z
date_published: 2021-11-17T00:00:00Z
date_updated: 2023-11-07T08:28:29Z
day: '17'
ddc:
- '519'
- '576'
degree_awarded: PhD
department:
- _id: GradSch
- _id: KrCh
doi: 10.15479/at:ista:10293
ec_funded: 1
file:
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checksum: 86a05b430756ca12ae8107b6e6f3c1e5
content_type: application/zip
creator: lschmid
date_created: 2021-11-18T12:41:46Z
date_updated: 2022-12-20T23:30:08Z
embargo_to: open_access
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file_name: submission_new.zip
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relation: source_file
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checksum: d940af042e94660c6b6a7b4f0b184d47
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date_created: 2021-11-18T12:59:15Z
date_updated: 2022-12-20T23:30:08Z
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has_accepted_license: '1'
language:
- iso: eng
month: '11'
oa: 1
oa_version: Published Version
page: '171'
project:
- _id: 2581B60A-B435-11E9-9278-68D0E5697425
call_identifier: FP7
grant_number: '279307'
name: 'Quantitative Graph Games: Theory and Applications'
- _id: 0599E47C-7A3F-11EA-A408-12923DDC885E
call_identifier: H2020
grant_number: '863818'
name: 'Formal Methods for Stochastic Models: Algorithms and Applications'
- _id: 25F42A32-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: Z211
name: The Wittgenstein Prize
- _id: 2584A770-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: P 23499-N23
name: Modern Graph Algorithmic Techniques in Formal Verification
- _id: 25832EC2-B435-11E9-9278-68D0E5697425
call_identifier: FWF
grant_number: S 11407_N23
name: Rigorous Systems Engineering
publication_identifier:
issn:
- 2663-337X
publication_status: published
publisher: Institute of Science and Technology Austria
related_material:
record:
- id: '9997'
relation: part_of_dissertation
status: public
- id: '2'
relation: part_of_dissertation
status: public
- id: '9402'
relation: part_of_dissertation
status: public
status: public
supervisor:
- first_name: Krishnendu
full_name: Chatterjee, Krishnendu
id: 2E5DCA20-F248-11E8-B48F-1D18A9856A87
last_name: Chatterjee
orcid: 0000-0002-4561-241X
title: Evolution of cooperation via (in)direct reciprocity under imperfect information
type: dissertation
user_id: c635000d-4b10-11ee-a964-aac5a93f6ac1
year: '2021'
...